Originally posted by franz32 does anyone know of any toy or gadget that interestingly uses thermodynamics or electircity?

There are these old toys that are available through "American Science and Surplus"www.sciplus.com

The toy is called something like "harbor putt-putt" boats. THey are small tin tugboats that run on a small votive candle that boils water in a chamber. LIttle bursts of steam are forced through the tail pipes and the boats motor around whatever body of water you got.

The same source has other things too, but these little boats are pretty cheap.